I've been entering a lot of contests online lately. Turns out there are blogs that do a lot of giveaways. I can't tell you which ones because I learn of them through Twitter and just go register. I can tell you most of them are mommybloggers.
Most of the contests are run through Rafflecopter. It allows the giver-away-er to set different tasks for entries and, presumably, randomizes the winner-pick. To start, you usually have to give your name or comment on the post or simply click OK. That then unlocks other tasks that give you additional entries. These include tweeting or sharing the contest, commenting on a non-giveaway blog post, liking the blog on facebook and/or following it on Twitter, etc.
It's this last one that I want to talk about. It makes sense that you would want people to like/follow YOUR blog. You are running the contest after all. Sometimes, there is a group of 6-12 blogs participating in the giveaway and you get an entry for each like/follow. I'm cool with that too. Often, however, you're given, say, 25 entries for liking/following all of the blogs listed on another page. There may be 25-50 blogs listed there. Some of them even have multiple pages of like/follow links! Are you hoping I will actually READ all of those blogs? I don't have that kind of time. Plus, it turns out, Facebook and Twitter get really cranky when you suddenly start liking or following a buttload of people all at once.
To accommodate this flood of internet noise I will likely ignore (unless you have another giveaway), I created contest accounts for Facebook and Twitter. That way I can skim through the flotsam and jetsam when I want to without disrupting my regular reads (or ticking off my followers with tweets about contests).
My guess on the multi-follows is they're trying to boost their numbers to get better advertising rates. For an iPad or a smart phone or anything else shiny, I'm happy to artificially inflate your numbers.