Correct...but when you don't justify it and it turns out to be terrible odds (sounds like you see that now), you shouldn't be surprised when you're called out on it
As for deflecting into irrelevant matters...90%+ of poker talk is chest thumping, and throwing a prop bet out is just a not-so-subtle way of doing it...again, you shouldn't be surprised that it draws comments.
With a few exceptions, nothing done here on SBR is a solid measure of skill....everyone's give-a-penetrate factor isn't at the same level, and there's not much reward to incentivize it.
However, if you'd like to make it worth something, I'd consider running a year-long version of the monthly contests I used to run. IIRC, you won one of those, so might be worth it for ya. How's 2500 points sound (on par with bowl contest)? Prizes 70/30 to 1st and 2nd, or maybe 60/25/15 for 1st/2nd/3rd?