On the back it says:
Energy 40kcal

Does that mean 40 thousand calories?
So 40kcal is 40 000 calories or what

It means 40 calories in nutritional terms, i.e., roughly equivalent to the calorie content in 10g of sugar.

There are two types of calories, chemistry calories, and food calories. The food calories are equal to 1,000 calories. Some food labels will list the calorie content in kcal’s in order to specify that they are referring to the food type. Most often seen on items imported from non-English speaking areas.

At $2.50 a can retail, I should be able to do better online. Beverages Direct doesn’t have it, and there website just directs you to 7-11 and "other fine retailers".
I go through about 2 cases of Red Bull/Go Fast/Bing per month, so I need a good price for quantity.

This is the site i have always been told to send people to for purchases in quantity. https://www.t-nation.com/productInfo.do?id=1273809

also, you might talk to 7-11’s in your area, if they will cut you a deal on a case. i have several stores that do that regularly for people. you might not get as good a price as from that website, but, you also wont have to pay for shipping. also, if you live in colorado, i may be able to point you in the right direction.

Are the high calorie,high sugar,high caffine energy drinks more harm than good? If I drink one just before cycling or running it seems to give me a little boost but I think it causes a big drop after 20 min. or so. Are the power bars any better? Is one brand better than the others?

I noticed a significant difference when I switched from water to a sports drink like Gatorade, not the energy drinks like Red Bull. I’ve never noticed a "crash," probably because once I started I kept drinking at a fairly regular rate. I bought the PowerBars but found their taste and texture to be obnoxious. I switched to Clif bars and have been happy with them. I regularly ride in events sponsored by one charity that seems to get donations of the GU protein gels. I’ve tried them and found them to be quick and effective but disgusting in texture and taste. I use them near the end of a century ride and they seem to help at that stage.

HTH