Walgreens does drug test. Hell almost every place does anymore! Yes even though you did fill out the W-4, they still might want you to pee in a test-tube on the first day of work! After that you should not have to take one unless you get hurt at work.
I am so sick of these drug tests for marijuana. They don't test for alcohol but with pot, hell yeah your outta here! How sad and pathetic the USofA has come. I remember a time not even having to worry about a drug test to get a job. I guess I am showing my age here! It wasn't that long ago either! Oh how I long for the days of old again!