Not to make you hard to respect
Just really really really really hard to impress
Lupe is saying he wants to get his sisters everything they could ever want, but not to make them spoiled, and turn them into brats, which would make it harder to respect them unlike someone who works hard for everything they have.
Rather so they are not easily impressed by showy guys and no man will ever be able to buy their attention. Instead men will have to impress them with their character rather than trying to buy them gifts.
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