If you want to split hairs, one is accurate and the other is a generalization. I think you might be making a mountain out of a molehill here.
But to be playfully pedantic here for just a second, people like you are the reason that bridges fall down.
I don't know about you, but I've never met anyone who would tell me "I bought this for 49.99" or "for 799". And with "tell me", I mean actually talking to me. It seems that when you're actually talking to someone, all the "99"s go away. It's when people write that all the nines are creeping in. I wonder why that is.
It's not a real issue of course. It's just that I go into facepalm mode every time I see someone do this and think: "Dude, $49.99 is practically $50, which is way easier to remember when thinking about price ranges." One cent in 50 dollars or one dollar in a 1000 dollars is not going to make any difference whatsoever. The only thing this achieves is making you look like you actually believe that 49.99 is really cheaper than 50 and 999 cheaper than 1000, as if this would put those products in different price ranges. It bloody doesn't!
I'd better stop now, have to watch my blood pressure.