This question is very straight forward: is there any reason for the Ichthys symbol to be almost always facing left? A simple google search will show this pattern.
Is there any theology or even symbolism for that?
Why is the Ichthys symbol almost always facing left?
No theological or symbolic reason seems to available as an answer. But I suspect that it may have to do something with the simple direction of which people are accustomed to write.
When text is added to the symbol, for example 'Jesus' or 'ΙΧΘΥΣ', aesthetically it looks better to have the first letter of in the mouth of the fish rather than its tail. (The opposite direction is true for right-to-left writing, such as Arabic or Hebrew.) - Which way should the Christian fish symbol face?.
Other possibilities do exist, but the reason stated above seems most logical and was in fact my first thought on this matter.