UH, BECAUSE IT'S GOOD FOR YOU.
If you read my last log, then you know all of the issues I've been having the past 6 months are muscle related. I started doing these little 20 min stretching routines this week and I already notice a major difference in my glutes, hamstrings, quads, etc. There are a billion diff videos to choose from with different exercises targeting different areas, I guarantee you will be able to find something that suits you.
SO, go, you get 7 days for free to try it out and if you think it's dumb, just cancel. But, I highly recommend you try it out, it can't hurt, right?