That can be a bit of a pain!What foods are you feeding as a main diet?Also,if you plan on feeding a homemade seed mix as your hamster's main diet then I don't think it would be a good idea as it is extremely difficult to know just what nutrition you give with one and even mixing two or more premade foods can be difficult
That being said,a homemade seed mix does make a wonderful treat.
Drs Foster and Smith have some really nice individual ingredients that can be used,not just seeds though as they have some fairly good dried fruits.Some of the fruit has added sugar,but not all of it does,however it is a lot better than some dried fruit you find which can have unsafe preservatives and even worse additives than just sugar.
If you have access to somewhere like Ross or Big Lots that can be a great place to find some healthier treats.It also can save you a lot of money,for example I've found flax seed that ends up costing over $5 in a grocery store yet in discount stores you can find it for around $3.I also found Gerber baby puffs,which ended up my Syrian's favorite treat,for about half the lowest price(they were only $1)and those are extremely healthy.Even though they have fruit as an ingredient there's barely any sugar as long as you don't feed something like 60 pieces(even then only a gram I think of sugar)and they go down much better than any storebought treat,which says a lot since my Syrian can be a bit picky and even shunned the popular but unhealthy yogurt drops
