Can I legally fetch tweets without twitter API?

Question

I am doing an RSS notifier, but I would like to add Twitter and Facebook feeds in it.
as both social networks shut down their RSS services, I am fetching the content
directly from the HTML public pages, parsing the content I want.

Question is: Is what I am doing legal?
Can I be sued for "stealing" information from their website?

PS: I know I could use Facebook or Twitter's API, but I don't want to log-in to their services.

Answer 1

Twitter's terms says the following:

Except as permitted through the Twitter Services, these Terms, or the terms provided on dev.twitter.com, you have to use the Twitter API if you want to reproduce, modify, create derivative works, distribute, sell, transfer, publicly display, publicly perform, transmit, or otherwise use the Twitter Services or Content on the Twitter Services.

[...]

You may not do any of the following while accessing or using the Services: (i) access, tamper with, or use non-public areas of the Services, Twitter’s computer systems, or the technical delivery systems of Twitter’s providers; (ii) probe, scan, or test the vulnerability of any system or network or breach or circumvent any security or authentication measures; (iii) access or search or attempt to access or search the Services by any means (automated or otherwise) other than through our currently available, published interfaces that are provided by Twitter (and only pursuant to the applicable terms and conditions), unless you have been specifically allowed to do so in a separate agreement with Twitter (NOTE: crawling the Services is permissible if done in accordance with the provisions of the robots.txt file, however, scraping the Services without the prior consent of Twitter is expressly prohibited); (iv) forge any TCP/IP packet header or any part of the header information in any email or posting, or in any way use the Services to send altered, deceptive or false source-identifying information; or (v) interfere with, or disrupt, (or attempt to do so), the access of any user, host or network, including, without limitation, sending a virus, overloading, flooding, spamming, mail-bombing the Services, or by scripting the creation of Content in such a manner as to interfere with or create an undue burden on the Services.

facebook is a bit harsher:

2. You will not engage in Automated Data Collection without Facebook's express written permission.

So just go and use the APIs meant for the explicit purpose of automatic data collection.