When I worked in e-commerce as a SRE, bots were doing two things:

- trying to disrupt business processes (eg: false referral listings, gift card scams, etc)

- trying to disrupt systems

I'm sure there are folks who use bots and scrapers for home automation, but these users generate marginal traffic in comparison. The real cost, aside from successfully achieving the points above, is the bandwidth and hardware costs that become overhead. Bots are usually coded with retry mechanisms and ways to change connection criteria on subsequent retries.