What you are missing here is that the Euro only works if the stronger countries support the weaker ones financially. Without this, the Euro could not be a stable currency.
If a country like Greece or Ireland is basically collapsing, it survives because countries like Germany and France pay for it. There is no such thing as a free lunch. What Germany gains now because of the weak Euro, it had to pay a few months ago to help Greece.
However, Greece has been paid by the government, not small businesses. Small businesses only have to bear that burden gradually by paying taxes.
Ireland and Greece were not supposed to be 'weak' countries.
Ireland just a few years ago was seen as a model for economic growth (supported by very low tax rates for companies). Ireland is a victim of its own misguided policies (housing bubble, banking system, ...) and its orientation to anglo-saxon economic policies.
Greece also failed to reform its economic policies (after cheating on the economic data for quite some time). There was time enough to do that.
I also don't think these countries are 'collapsing'. But adjusting their economic policies will be tough.
Sure, they did not collapse actually. But their economy very nearly did. Both Greeces and Irelands economy basically only survived because the rest of Europe paid for it. And I think this is a good thing. Europe is a better place if we help each other.
Of course, no country in the Euro zone is supposed to be a weak country. After all, investing so much money in Greece and Ireland is a testament that Europe indeed does believe that these countries can get back on their feet.
If a country like Greece or Ireland is basically collapsing, it survives because countries like Germany and France pay for it. There is no such thing as a free lunch. What Germany gains now because of the weak Euro, it had to pay a few months ago to help Greece.
However, Greece has been paid by the government, not small businesses. Small businesses only have to bear that burden gradually by paying taxes.