I work at a competitor to best buy that offers Tech services.
Tech services are just like car services. If you don't know how to do it, or you don't want to do it, you may consider paying someone money to do it for you. There are people who pay for oil changes, or even changing of an air filter (if you can lift your hood to your car you can change an air filter).
You're paying for the following:
*Knowledge to do what needs to be done
*The actual time it took to do the work
*The renting of tools to do the job (in this case only the internet connection, and router and cables and such that provided such) Those tools have a cost. They need to be paid for. They work for several work orders, but eventually need to be replaced - it's a cost of offering the service.
*The liability factor in case 1) something goes wrong or 2) your customer is dead-set on suing you simply because you had their property. (Of course, geek squad is exempt from this because they aren't honest. If they have a human error moment they'll claim it's a problem with the customer's unit and will charge them even more to make up for their mistake)
Yes, when it's something we know how to do, it may look stupid... but there are a lot of people who simply don't know and don't want to know, and the only way they can get it done is to pay someone else to do it. Even if it's something as simple as tying your shoes... Hmmm. I can now see shoe stores offering a service to put your shoes on and tie them for you.
$30 dollars for a service that you are in NO WAY obligated to buy doesn't sound bad. It's your money. Spend it how you want. If you don't need a service, don't buy it. If you want someone else to do it because you know nothing of computers (which is STILL very prevalent in this day and age) they offer the service.
It's a chuckle for us knowledgeable people, but working in retail a lot of people lack an abundance of knowledge.... an abundance of anything in their head actually.