Yes, unfortunately in many Arab/Asian countries people over-indulge at Iftar time. It seems less of an issue for "converts" of different origins = more of a cultural thing, as Muhammad -saws- encouraged people to eat and drink moderately, and certainly not over-indulge in a month like Ramadan.

Some people, including me, avoid this though. When I was obese (for different reasons), I used to lose 3 or 4 kilograms each Ramadan, but failed to sustain that once the month was over because of my previously terrible lifestyle. My mother also gets leaner during Ramadan because she prepares her own healthy Iftar (mostly Harira, a Moroccan soup, some figs, whole-grains bread and other "sane" alternatives to oily/sugary food)