Businesses that started before the advent of cloud software will continue to use QuickBooks because that's what the owners know, and why fix something that isn't broken? But newer businesses that started in the last few years will be much more likely to use cloud software because it's so much more convenient.
One of the accountants I know considers herself computer savvy (she's not, but that's a different topic) and she's pretty young (30s) and she insisted I build her a server for her business to run Quickbooks off of. She won't trust a cloud solution, or even a remotely hosted server. Some of this fear seems to be based on the seminars she goes to which are either held by or attended by FBI special agents. They are pretty good at telling you all the ways you may be hacked, and precious little practical advice on how to avoid that while staying sane.