Without focusing on your opinions (the whole 170 thing isn't the point of the question, people) I'll try to answer as best I can. Hopefully. :)
I only like it if the girl in question is pregnant. If they aren't, and they have muffin tops spilling out from under their shirt, and over their jeans, it's generally disgusting.
I'm fat - and I deal with it. I wear clothing that keeps me covered. Showing skin - even muffin tops, in some cases - is only sexy when it's meant to be sexy. You know, when the person is wearing a revealing summer top or formal wear cut high at the sides, etc.
When it's just someone waddling to-and-fro while simultaneously spilling out from under their clothes, it's disgusting. Well, that's actually a bit harsh. It's not that bad. It's just unattractive. To me, anyway.
Opinions vary though, like you said, and there are bound to be people who enjoy it, even advocate it I guess. It's a unique world, with plenty of unique people in it. :)
Most guys don't mind a girl who's a bit bigger than average and at the right height and build I'm sure 170 isn't too big but I don't think there are very many guys or girls that prefer that build over a more fit toned one. For that reason I don't think showing off excess fat is a good one. If people are only somewhat overweight and wear it well they look a lot better without the pudge.
Some guys have a fat girl fetish, I personally don't like mushroom tops. Hell, even if you do have pudge that will bubble out from all sides in tight jeans that will make your stomach look like the top of a mushroom, as long as you wear clothes that ACTUALLY FIT YOU and you are stylish and have grace and elegance to you, I'd date you.
170 may be totally normal for some girls, especially if they are tall with a broad body shape.
Jeans are tough, so long as the zipper zips and it lies flat (zipper seam lies flat so you can't see the zipper at all) then its good. Any looser and they aren't flattering either. There are mid rise jeans which can be an option for some, but not so much for short girls who already have a short torso.
Men like different things, its about what YOU feel comfortable in. If you feel like you look hot in that outfit, wear it. If you dont, go get fitted for some cute jeans and tee's and flaunt what you've got.
I'm fat and I hate having a muffin top. If my pants give me a muffin top I will not wear them at all. I'm lucky that even though I'm over weight I have don't have a huge stomach, it's actually rather flat.
I don't think it's gross though, it's just not flattering.
Even so, when "skinny girls" have a muffin top they look bad too. Muffin tops are not good in general.
Yea 170 really isn't that much, though it would be nice if people wore clothes appropriate for their body type..they can still wear whatever they want just be more conscious (know what accentuates their shape best). I was at the mall the other day and there was a girl my age wearing spandex tights and a a mid drift top that like basically just covered her boobs..there was extreme muffin top and back hair.. lmao it was pretty gross. I totally wonder what she was thinking when she put it on :/
it depends on how tall you are because if you 5'11 and you are 170 then your stomach will most likely be flat but if you are 170 and 5'0 then you probably look fat. However it would look really unattractive depending on the guy or really sexy it depends on the person
Let them. It's not your body, and not your problem. They feel good about themselves, and thats great! Who are we to judge, how they should dress? You don't like how they look, then don't look like them. Just leave them be. I don't think it's pretty either, but I don't give a shit, about how other people look. It's none of my business.