It restricts the suggestion to go shopping to a specific chain of shops, so in that sense it modifies it.

Student or Learner
Please do not be upset and disappointed with this question. I just want to listen to native English speakers' thoughts.
"Let's go shopping at Walmart."
Here in the sentence, do you think that at Walmart modifies go shopping or do you have another idea? Thank you so much as usual and I hope to hear from you.
It restricts the suggestion to go shopping to a specific chain of shops, so in that sense it modifies it.
Thank you so much and "it modifies it" means "at Walmart modifies go shopping"? Did I get you right? Thank you again.
Let's (suggestion) + go shopping (activity) at Walmart (restriction of activity to a certain place)
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