They drive me nuts, too. So I've been looking for a good solution and think I've found it. I tried using needle top caps, but the darn things had such a tiny gauge needle that they drove me just as nuts. But yesterday I was browsing at One Stop DIY Shop and found that they sell luer lock bottle caps for $.75:
Colored 1 oz Luer Lock Bottle Cap - One Stop DIY Shop Store, LLC
I ordered 6 of those, then I ordered some 1/2" 18 gauge blunt tip needles, which they have for $.50:
Blunt Tip Needle - One Stop DIY Shop Store, LLC
They also have bottles with the luer lock cap and 18 gauge needle for $1.75. So I bought some of those, too:
Boston Round Bottles with Luer Lock Cap and 18g Needle - One Stop DIY Shop Store, LLC
I should have them in a few days and this will HOPEFULLY solve that problem once and for all. I'm sure juice will go through those needles easily, but if not, I'll just get some 16 or 14 gauge needles and use those.