I imagine that's just the market. Nearly everyone charges around $30, and it's not completely unreasonable. I've seen some variation in those costs, though, and there's a lot of variation in costs of add-on features.
We ended up going with desk.com. What we found nice there is that you get one free agent every month, plus a concept of a "flex agent." Flex agents cost $1/hour, and desk.com gives you quite a lot of free flex time when signing up and doing a few tasks (plus the occasional grant of flex time as you use the product). There's only two of us, and we haven't had to pay a dime yet, going on I think 6 months.
On the other hand, they charge $50/month for a full-time agent (unlimited usage, basically), so it really depends on how many people are going to use the site and how often.
We ended up going with desk.com. What we found nice there is that you get one free agent every month, plus a concept of a "flex agent." Flex agents cost $1/hour, and desk.com gives you quite a lot of free flex time when signing up and doing a few tasks (plus the occasional grant of flex time as you use the product). There's only two of us, and we haven't had to pay a dime yet, going on I think 6 months.
On the other hand, they charge $50/month for a full-time agent (unlimited usage, basically), so it really depends on how many people are going to use the site and how often.