indeed. $10 a month sounds reasonable, but $10 a day is super expensive.

electricity costs (where i live) $0.10 /KW/h. so * 24 = $2.4 per day.
it's not necessary to have high speed internet, so a cheap DSL line (@$30 a month, $1 per day) will do. you can probably have multiple machines running on the same line, because bitcoin mining isn't bandwidth intensive, so it's probably less than $1 a day. that leaves ~$6 per day for managing the servers, which is pretty expensive considering setting up mining rigs isn't very hard.