I would be okay with spontaneous visits if I were retired. Currently, if friends just show up I would have to turn them away from time to time (or they might find an empty home).
It seems more like something out of respect that you would do. Even with family, I feel it is respectful so, I always call ahead. I do not get upset when people show up on whim, but I will feel a little bad when I have to turn them away. Sometimes I don't and have to feel the frustration of accommodating them. I don't make that their burden, it is mine if I accept the situation. It is still an awkward emotional space to inhabit. In the age where everyone has cellphones it seems unreasonable that someone could not call and see if you would be available for them.
There is a caveat for emergencies. Also, there are friends that I let know that they can bother me when they want/need me. My best friend is 75 and in ill health. There is no situation I would not make time for him.
It is better to be informed because first, I have a time to create a plan for him or her. For example,, I can arrange an outing program with him or her, if s/he informed me before. Second, maybe I have a plan to do that I couldn't cancel for him or her.
You are homies so that is cool
aint nobody got time to call
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