I know that it's probably not the best place to ask the question, but I'll give a short question as an answer. Why? I know of some that prefer this method, but most cite the ritual of doing it as the most enjoyable aspect. The equipment and the process are fun in theory, but are a hassle in everyday life. There are plenty of people that enjoy the hobby as much as the necessity (see 12345Michael's link), but I've never been able to fully embrace it due to the time and skills it takes to keep up with it, let alone some of the expense.
If you're looking for an alternative to disposable razors, try out a safety razor. It's not complicated to learn, you have a wide array of luxury tools to purchase and you have inexpensive blades to swap in your expensive shaver.
I've personally found it to irritate my skin less and to get a closer shave as I can control the angles better. Just my .02.