[hnarn]

> if non IT companies had their own IT department

I think you vastly underestimate the cost of on-prem IT, especially for small and medium sized businesses. The "floor" cost of your own IT is many, many orders of magnitude higher than a subscription to something like Office 365 for something like 50 people.

"Normal" people don't use cloud services because they're lazy, they do it because the economics of rolling your own IT does not make sense, and hasn't since the days when it stopped being your only option.