n.b. I'm honored to be included in that august company, but just to avoid people getting the wrong impression, Appointment Reminder is quite a bit smaller than every product on that list.
With regards to the larger point: there are many, many ways to successfully take money from customers.
If you want to build a business mostly on the $20 to $50 per month low-touch SaaS model, you can do that, quite successfully. (ConstantContact, 37signals, SmugMug, etc)
If you want to build a business which addresses customers with low-to-medium touch sales and costs between $25 and $X,000 per month, you can do that.
If you want to build a business which dogfights for $75k to $250k a year enterprise deals, you can do that. (Welcome to the world of boring enterprise software, where there exists surprisingly little visibility since the relevant people don't blog so often, but it basically makes the world go round.)
If you want to do a hybrid low-touch model in the $20 to $50 space, mid-touch in the $X00 to $X,000 a month space, and high-touch in the Enterprise space, you can do that, too. (Some companies move there after discovering that the mathematics of the low-end model are a bit painful if you happen to hit constraints on e.g. market size.)
With regards to the larger point: there are many, many ways to successfully take money from customers.
If you want to build a business mostly on the $20 to $50 per month low-touch SaaS model, you can do that, quite successfully. (ConstantContact, 37signals, SmugMug, etc)
If you want to build a business which addresses customers with low-to-medium touch sales and costs between $25 and $X,000 per month, you can do that.
If you want to build a business which dogfights for $75k to $250k a year enterprise deals, you can do that. (Welcome to the world of boring enterprise software, where there exists surprisingly little visibility since the relevant people don't blog so often, but it basically makes the world go round.)
If you want to do a hybrid low-touch model in the $20 to $50 space, mid-touch in the $X00 to $X,000 a month space, and high-touch in the Enterprise space, you can do that, too. (Some companies move there after discovering that the mathematics of the low-end model are a bit painful if you happen to hit constraints on e.g. market size.)