Nice that you only got a warning... Very civil...
I often park in the hashmarked slots at the end of diagonal parking rows,.. to save full parking spaces for cars...
Just a few times, I've been told not to... but most places encourage it... They don't want you want wasting a full space either..,
Just depends on the a-hole in charge...

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We bikers are "special needs"... in that we don't need much, as far as parking is concerned...
Don't you love places that have motorcycle parking?...

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