| there are many people who do all sorts of jobs and plays in bands over the weekends. Alot will depend also on the type of music. One of my highschool friends is a electrical engineer but also owns a recording studio and plays in a band on weekends.
But if you want a music career to really go somewhere, you have to put it first, you would go to college for music if you want to stay in music and go to college, perhaps be a music teacher or be a private music teacher.
Since as you find places to play, you have to be available to travel and play various days of the week.
An example my wife played last Monday in a coffee house about 120 miles away from home. On Wednesday she played at a church conference meeting here in town, but it was at 11 am and this Fri, Sat and Sunday, she had several play times in nashville each day( about 100 miles away) so for her, having a regular 9 to 5 job just will not work, since she had to leave early on Monday, stay overnight since the performance ended late, had to perform during the day, and then be gone for several days in nashville.
had she had a regular 9 to 5, she would have had to turn down most of these, or at best drive home late, go on little sleep and so on.
Often doing some business of your own, where you can set your own hours may work for you. | 
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