Your point is correct- supplements are useless IMHO. Also check the label, they are probably potassium chloride, and you probably need natural fruit potassium (which is potassium citrate, potassium phosphate and others). The natural potassium is plentiful in black beans and other similar beans, fruits, vegetables (avoid peas and corn and green beans though, in my opinion). If you are on any medication you should check with your doctor first, because some drugs affect your potassium excretion. Also chronic kidney disease can do the same thing and cause potentially dangerously high potassium levels in the blood. If you are manipulating your potassium, it's probably wise to get blood tested periodically. Good luck.