Looking for opinions

Okay, so I am looking for peoples opinions on this situation.

Job A hired me on April 6th. Job B hired me on April 23rd. Those were my starting dates.

Job A pays 25 cents less per hour than Job B.

The first 4 weeks I worked for Job A I have 2-4 scheduled shifts a week and the weeks I had only 2 they offered me another shift. Then all of a sudden they dropped me to only 1 five hour shift for 3 weeks straight, a 2 shift week, then several more weeks of 1 shift, then last week 3 shifts. BUT, on Thursday called and told me my shift on Friday was canceled because the store didn't have the hours for it.

Job B has consistently given me 4 shifts a week, occasionally a 5th as well. And I consistently work 20-24 hours a week there. Sometimes more. Job B has just promoted me which will mean another raise.

Job B has stated that if I open my availability I can probably have more hours per week once my training is complete.

Job A gives me a 25% discount on clothing for the whole family. This is a brand I like. Job B gives me a 15% discount on STORE BRAND products.

My issue is...

Yesterday I went to both stores to get my schedule. Job B has given me 27 hours (WOOHOO) and Job A has given me... NADA. Not a single shift. The general manager said that the shipment is slow this week.

I really feel about ready to give my 2 week notice. I am torn though because this is a national company with a good record overall. But I'm making less money and not even getting hours. I get a generous discount and would DEFINITELY miss that. But there's other ways to get my clothes for less money.

SO... please weigh in with your thoughts. What would YOU do? What do you think I should do? And why please.

Thanks everyone!