If a fake profile gets flagged once or twice not much will happen. If a profile gets flagged several times it will get the attention of the moderators and that profile will disappear. While it may seem like a never ending battle, just ignoring all these fake profiles would just totally clog this site with them. The fakes are pretty easy to spot. They usually show up in the notifications (the little bell symbol in the right hand side of the blue header at the top of the page) as "likes your profile" Usually a young attractive woman or gay man (that you have probably seen the picture before) Joined in the past few weeks, very little or no stats and their description almost always steers to a website. If more members flagged the fakes and reported them here for other members to check out and if they believe them to be fake do likewise, while the problem will not be eliminated at least it can be controlled
Not always bots.. Some of these sites have "incentive / commission" programs for recruiting new members. Usually, depending on the volume of members these people are trying to recruit, they can be a little more creative and more difficult to spot.