Over the past few years, Berlin has become a hot tourist destination. This rapid increase in tourism, and the negatives it brings, has made some locals angry, especially in Kreuzberg, which has become a tourism mecca. You see "Berlin Doesn't Love You" signs everywhere.
Personally, I like tourists. They add a festive element to the city; and for the most part, they're respectful and law abiding. Nevertheless, tourism does have its drawbacks, including an increase in crime, drug and alcohol abuse, and, of course, litter. After the holiday is over, there will be trash, broken beer bottles, cigarette butts, and discarded pizza cartons scattered everywhere. It makes riding a bicycle dangerous.