I don’t really want to pursue this argument further, especially because I don’t actually think you are racist (or not more so than the rest of us). The last thing I will do, though, is explain *why* I think the *joke* is racist (not the samer thing as saying you are).
It was not the gag about the bindi that annoyed me: for a start, I think superstitious beliefs are *always* a fair target for humour, regardless of the culture with which they are associated. The bit I think is racist is the joke’s inference that indian hindus are all dying to go to America, that all those who do so end up running convenience stores, gas station, donut shops, or motels (ie taking jobs which the average American could do etc etc), and that those who are unlucky get stuck in India working in an industry which is associated with (a) causing Americans huge frustration and (b) taking American jobs (again).
I think the idea of the bindi as a scratchcard lottery is quite funny; the fact that the punchline relies on racist (or, at least, prejudice-driven) sterotypes robs the joke of its humour, at least for me.
FWIW, here’s how I first heard the joke - as a shaggy dog story:
This bum was sorting through junk in his city’s dump, looking for anything he might be able to flog for a few pennies - iron for the scrap merchant, old clothes that still had some wear in them, anything - when he saw the glint of a silvery metal. He trudged over to check it out, but though he was expecting little more than yet another baked-bean tin he was surprised to find something that looked a little like a rather ornate, miniaturized oil-can. Wondering what metal it might be made of, he tried to polish it up a little with his sleeve… And (surprise!) out rushed a fog of smoke that rapidly formed into the shape of a gigantic, beturbanned genie.
“Ooooh, that’s better!”, boomed the genie. “Two hundred bloody years I’ve been in that damned thing! Last time that blasted bleeding lamp was found, I thought Here we go!, but nope, no spit-and-polish cleaning, this is the age of electrolyte immersion no-rub silver pol;ish or what have you, stupid damned invention if you ask me…”
Here the bum interrupted the tirade.
“‘Ere, I’ve seen you in that movie! Aren’t you supposed to say ‘I am youir slave anmd am ready to obey?’”
“Listen, chum, if you’d spent 200 years in a bleeding lamp you wouldn’t be too quick to make yourself someone’s slave, OK? In the old days, sure, I was in and out of that thing all the time, no problem. But times have changed, I’m ee-man-sip-ated now. But look, since you let me out here’s what I’ll do: one perfect day. That’s what I’m giving you. Absolute luck, for this one day only.” And with that, the genie vanished.
The bum shook his head, wondering if that was what came of too many cartons of cheap Rhiesling - and caught sight of a glint of gold in the muck. He investigated… and found a small but heavy statuette. Breathless with excitement, he rushed it to the nearest jeweller’s: assayed, it was found to be solid gold, worth a year’s stay in the Ritz! Anhd that was just the start of his good fortune… lottery tickets came up jackpot, one-armed bandits spewed forth coins, cheap bottlesa of wine turned out to be clumsily mislabelled Chateau-Lafitte ‘77, people even stopped pretending they couldn’t see him!
The day drew to a close, and just as he was wondering where to spend the night - should he wander down to the Palace and try his luck there? - a beautiful Indian girl approached him. She turned out to have mistaken him for someone else, but once they has resolved thwe amusing mistake she found herself chamed by this humble, slightly confused, but very happy (and evidently wealthy) companion. They chatted for ages, retiring first to a bar, then a restaurant, then - our lucky hero could not believe his luck - to bed, where they canoodled, and even kayakked. In the uninhibited post-coital glow, he asked his beautiful companion about the painted spot on her forehead. Blushing, she explained that it was the mark of a virgin.
“But,” she breathed, “Now you have initiated me into the loving arts… it is your privelege to scratch it off.”
So he did - and won a car.