Peel Regional Police say they got a call shortly after 4 p.m. about a customer who had just left a Beer Store on Main Street.
Const. Lillian Fitzpatrick told CBC News that staff saw the man go toward a vehicle, which prompted them to phone police.
The staff provided licence plate information, which helped police catch up with the alleged impaired driver a short distance from his home.
The man charged is in his 40s, Fitzpatrick said.