Why do companies like Best Buy etc send texts and make people think they have won something and send them on wild goose chases on the web??

Because it wasn't sent by Best Buy. It was sent by an internet scammer who banks on the fact that a certain percentage of people are gullible, will believe anything and will give away their personal info to get a non existent "prize". Simply by going to the website they provided, you could have already infected your computer with a virus that will steal your personal information, credit card numbers, address book and God only knows what else.