It's a hobby. I do this during some downtime/free time, like watching sports (it's really easy to read these boards and blogs during baseball). I fly less than you OP, and I have over 15K miles for US Air, and 10K Hilton. I've spent less than $50 on things I didn't need or paid a dollar or two more for a purchase just to get the miles. People would probably tell me that my miles will devalue, but for me it's a hobby. I'll keep the accounts active as best I can, maybe sign up for a credit card or two eventually, and someday take some free trips. If you're time is too valuable (and only you can decide that), then it's not worth it.