From the software vendors' perspective, it makes good business sense to call you asap, see: http://blog.close.io/why-you-need-to-call-every-signup-user-...

From a customer perspective, ideally that call will help you to save time by: a) figuring out faster if this software is right for you or not b) helping you to learn how to use it the best way possible c) setting this up so you make the most out of your trial.

I'd rather take objection with bad sales calls, not with the fact that they call on the same day.