Juveniles of most fish are non-territorial because they don't need to exhibit any broodcare behaviour or compete for mates. Furthermore, sensitive fish like spiny eels will be scared when kept in retailers' tanks, so their behaviour is abnormal anyway. So don't read too much into what you're seeing in the pet store.
Fire eels have been kept in groups, but only in public aquaria with volumes measured in the thousands of gallons. For all practical purposes treat them as territorial, aggressive fish best kept alone. If you want to keep spiny eels in groups, look at the genus
Macrognathus instead; on the whole these are much more easy-going.
Cheers, Neale
if they are babies and were in the same tank and the same size?and they always slept together or hid together ? even though theres alot of places to hide?and if 1 goes to eat the other follows behind him/her? and they are always together???