Would be an epic fail, a lot of resources, time, money for what? Banning Top Eleven players, killing part of their revenue? No way, this is not gonna happen.
If you give some freedom to the people, there would always be those who would abuse it so better no. Plus some of the emblems of logos would be very likely on the rules but far from looking as a normal football logo so you would not have a feeling of playing vs a football team but against I don't know who.
Also would be quite hard for Top11 to decide which pictures uploaded can be used or not, nobody would stay and search to see if some of them are allowed or not despite technically they can avoid all these issues by making you directly resp. for what you upload but as I said, people would not buy anymore officials or the current premium ones and they will focus more on some custom ones.