Seriously, yes...read the Serious Fish link.
Most fish will be tempted to eat anything tiny enough to fit in their mouths, but there are many exceptions to this rule.
For example, my Dwarf Gourami could eat shrimplets and chilli rasbora, but he isn't interested.
The real issue with the Pearl and tetra mix is the differing levels of activity, with all gourami preferring quieter, more settled tankmates. Rasboras and some barbs, (Harlequin and Cherry, for example), are a better mix and I'm sure that it's not just a convenience that they originate from the same areas.