Not sure why they are completely different animals. Both protect property rights in creative work which can be easily copied/replicated (without attribution or compensation).
As for abolishing software patents -- would help if you can list the reasons people cite -- I can't offer a counterargument otherwise.
Too much ink has been spilled on this topic but most arguments against software patents continue to be patently confused and unelightened about the core matters. For one, patents do not exist purely to 'incentivize', but also for reasons of fairness and justice. If software patents should be abolished, why exactly do we need copyright laws? Why don't we allow any book/paper/poem to be copied and resold by anyone under their own name? Why don't we allow people to make derivative copies of say harry potter books and build their own fortune? Im sure society wont be worse off for it.
Second, the problem with the patent system isn't that patents are given too easily (trust me, its not that easy), or to obvious things -- as they say, all beautiful solutions are obvious in hindsight -- but that companies that infringe patents have convinced themselves that they are within their right to do so. There's definitely a strong case for giving immunity to companies below a certain size (revenue, employee base etc) from patent prosecution, but most large companies can easily license patents but refuse to. Yes, there are still abuses of the system, but those are bound to arise no matter what system you put in place.. someone will always try to game it. And as software patents are litigated, common law will settle down on standards and businesses will know whats kosher and whats not. Much of the current excitement is because we are currently in the midst of the first explosion in assertion of software patents where common law is still evolving.
Last, many of the claims being made regarding the supposed absurdity of apple's patent claims are so fundamentally (or willfully?) uninformed, that it begs wonder (not very unlike the willful distortion of news from other countries thats so common in major western news platforms). Apple never really asserted a patent on a rectanle with round edges.. and as for its claims on UI elements -- it was a trade dress claim primarily, not patent claim. The bounce back and tap to zoom claims were patent claims -- but rest assured, micrsoft would probably have implemented the same with no bounce back and context menus to zoom. (no ms office app after 30+ yrs in mkt still has bounce back -- so maybe its not that obvious). However, the prior art arguments are legitimate and can only be settled in court.. which samsung simply failed to do.
As for abolishing software patents -- would help if you can list the reasons people cite -- I can't offer a counterargument otherwise.