These tools let you set up lots of landing pages for cheap (or free), collect tens or hundreds of thousands of leads, do split testing, then export into whatever the next step of your process is. At a basic level, these products are ways to have a prospective customer fill out a form, for some later use.
Landing page software is great if you're in a product business, collecting early stage feedback. But, most people don't set up landing pages and collect tens or hundreds of thousands of viral leads a month - for a freelancer or small consultancy, you need a more personal touch. For a product business, you may be generating dozens or hundreds of leads from your website, and need a way to organize them. With a tool like Osmosis, you can still put a form on a website, but you track each customer or prospect on an individual level.
Once a client has filled out your questionnaire, you can use the information provided to build a work agreement, proposal, or terms of service, as needed. This works well for project based businesses, and even many smaller product businesses collecting feedback from early customers - we even use our own questionnaires to collect feedback about our product. Still have doubts? Unlike free tools, we're priced so that we can give exceptional support to each of our clients.