Almost without fail, I get asked this question multiple times at the end of the week. Why do you people ask you what you are doing this weekend?
If the people are your friends or know you well, most likely they genuinely care about what you are doing. Maybe they want to know if you are doing something cool so that they can join you. Maybe they have tips or advice about a place you are traveling to or an activity you are trying for the first time.
A more cynical person might argue that people ask this question because THEY have something good planned for the weekend, and THEY want YOU to ask THEM so they can tell YOU about it.
Regardless of the reason, I have a different question. Why don't people ask you what you are doing on a specific day during the week? "Hey Claude, what are you doing this Tuesday?" That's usually a preface for an invite to an event. But why do we care about what people are doing on weekends and not so much about what people are doing during the week?
You probably know the answer. In our culture of work, most people have a JOB and work Monday-Friday. Who wants to hear about that? I would be curious to talk to someone who regularly works weekends and ask that person if they still get asked what they are doing on the weekend.