It’s only “correct” in that it has become ubiquitous through usage.
What you are describing is called “language”
“You” wasn’t always allowed to be singular. Colour vs color. Doughnut can be donut. Etc. Languages evolve over time, and “drive-thru” is in plenty of dictionaries.
What you are describing is called “language”
“You” wasn’t always allowed to be singular. Colour vs color. Doughnut can be donut. Etc. Languages evolve over time, and “drive-thru” is in plenty of dictionaries.
Yup, “drive through” is an instruction, “drive-thru” is a noun. So you’ll drive through the drive-thru.