Cigarette companies spent a lot of money on advertising [in Europe]. When cigarette ads were banned, they continued to sell cigarettes, but saved on the marketing budget. Still, it would not have been wise not to advertise beforehand: The level playing field is all that matters. For some reasons, e-cigarettes are allowed to advertise, and the shift to these products is substantial.

So for sales/consulting, it might be fine not to travel to your customer when nobody can. Afterwards, you might want to reevaluate.

(And I am speaking as an ex-consultant that hated corporate travel).