Donald Trump met in Washington, D.C., with a gathering of top business leaders who were reportedly surprised by what they encountered. The former president and presumptive Republican nominee spoke Thursday at Business Roundtable’s quarterly meeting, where he promised to cut taxes and roll back regulations if re-elected – and got laughed at for suggesting eliminating taxes on tips – but CNBC’s Andrew Sorkin said some of the CEOs were alarmed by his behavior during the event. “I will say I was surprised,” Sorkin told “Squawk Box.” “I spoke to a number of CEOs who I would say walked into the meet…