When Alcmene hallucinates about Hercules, approaches and walks right through him, you can clearly see he is wearing his leather forearm protectors.
In the next shot, right after passing through him, as she turns around to him, and he faces her, he is not wearing them anymore.
In the next shot, after a few closeups where his arms aren't shown, he's wearing them again.
Falafel offers to make Hercules a birthday cake and asks if he likes chocolate. Chocolate is native only to South and Central America, and was not introduced to Europe until the 16th century AD.