Is it harder to find pokemon with a higher-level party leader?

[Symphonic.x.Fantasia]

Let me explain: Whenever I'm on one of the first routes, catching fodder pokemon, it seems harder to find them the higher my team leader's level is. Is it my imagination?

 

[empty streets]

No, it's not.
But if it is, then we're both halucinating xD

 

[rockman0]

it seems the same way to me.